I'll leave it to you to figure out if it will physically fit and if you have the needed psu.
My current computer's video card is very lame and I can't play high graphic games. I only get about 3-5 FPS on these games and really need a good one that can play these at high quality (or something around there). I am willing to spend about $100-$150 on a video card.
My computer specs are:
AMD FX(tm)-4100 Quad-Core Processor
16 GB Memory
64 bit - Windows 7 Home Premium
(Forgot my video card)